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AIM: The aim of this study was to determine the impact of asthma and air pollution on school attendance of primary school children 6 to 12 years of age in Qatar. STUDY DESIGN: This was a cross-sectional population-based study. SUBJECTS: The total 31,400 Qatari school children at the primary school (16,130 boys and 15,270 girls) 6 to 12 of age were studied to investigate school absenteeism caused by asthma and wheezing during the academic year October 2003 to July 2004. METHODS: We have used the School Health Registry for obtaining the student information and school absenteeism due to asthma and wheezing. Again we had double confirmation on the data obtained on asthmatic children by using the modified version of the International Study of Asthma and Allergies in Childhood [ISAAC] questionnaire. RESULTS: A total of 3,270 (10.4%) pupils were diagnosed as having asthma and wheezing. Overall 2,516 (8.02%) pupils were absent from the school for at least one day during the year. There was a statistically significant difference between asthmatic and wheezing students in number of days absent from the school (p < 0.0001). Most absenteeism occurred during spring for both boys (45%) and girls (47%), followed by autumn for boys (33%) and girls (36%). The measured pollutants reached a peak during the spring season and then in autumn of the studied academic year. CONCLUSION: Children with known asthma miss more days of school than those who do not have asthma. This study finding shows that air pollution has an impact on asthma, which results in significant school absenteeism. 相似文献
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Kevin O'Brien Jean Wright Frances Conboy YeWeng Sanjie Nicky Mandall Stephen Chadwick Ivan Connolly Paul Cook David Birnie Mark Hammond Nigel Harradine David Lewis Cathy McDade Laura Mitchell Alison Murray Julian O'Neill Mike Read Stephen Robinson Dai Roberts-Harry Jonathan Sandler Ian Shaw 《American journal of orthodontics and dentofacial orthopedics》2003,124(3):234-43; quiz 339
This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant. 相似文献
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Alleles of RUNX2/CBFA1 gene are associated with differences in bone mineral density and risk of fracture. 总被引:4,自引:0,他引:4
Tanya Vaughan Julie A Pasco Mark A Kotowicz Geoff C Nicholson Nigel A Morrison 《Journal of bone and mineral research》2002,17(8):1527-1534
The aim of this study was to determine if DNA polymorphism within runt-related gene 2 (RUNX2)/core binding factor A1 (CBFA1) is related to bone mineral density (BMD). RUNX2 contains a glutamine-alanine repeat where mutations causing cleidocranial dysplasia (CCD) have been observed. Two common variants were detected within the alanine repeat: an 18-bp deletion and a synonymous alanine codon polymorphism with alleles GCA and GCG (noted as A and G alleles, respectively). In addition, rare mutations that may be related to low BMD were observed within the glutamine repeat. In 495 randomly selected women of the Geelong Osteoporosis Study (GOS), the A allele was associated with higher BMD at all sites tested. The effect was maximal at the ultradistal (UD) radius (p = 0.001). In a separate fracture study, the A allele was significantly protective against Colles' fracture in elderly women but not spine and hip fracture. The A allele was associated with increased BMD and was protective against a common form of osteoporotic fracture, suggesting that RUNX2 variants may be related to genetic effects on BMD and osteoporosis. 相似文献
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Clare E Herbert Martin A Ebert D Barclay David S Whittall David J Joseph Chris S Harper Nigel A Spry 《Medical Dosimetry》2003,28(1):27-30
A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate. 相似文献
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Henryk J Salacinski Nigel R Tai Robert J Carson Alan Edwards George Hamilton Alexander M Seifalian 《Journal of biomedical materials research》2002,59(2):207-218
Poly(ester)urethane and poly(ether)urethane vascular grafts fail in vivo because of hydrolytic and oxidative degradative mechanisms. Studies have shown that poly(carbonate)urethanes have enhanced resistance. There is still a need for a viable, nonrigid, small-diameter, synthetic vascular graft. In this study, we sought to confirm this by exposing a novel formulation of compliant poly(carbonate-urea)urethane (CPU) manufactured by an innovative process, resulting in a stress-free. Small-diameter prosthesis, and a conventional poly(ether)urethane Pulse-Tec graft known to readily undergo oxidation in a variety of degradative solutions, and we assessed them for the development of oxidative and hydrolytic degradation, changes in elastic properties, and chemical stability. To simulate the in vivo environment, we used buffered solutions of phospholipase A(2) and cholesterol esterase; solutions of H(2)O(2)/CoCl(2), t-butyl peroxide/CoCl(2) (t-but/CoCl(2)), and glutathione/t-butyl peroxide/CoCl(2) (Glut/t-but/CoCl(2)); and plasma fractions I-IV, which were derived from fresh human plasma centrifuged in poly(ethylene glycol). To act as a negative control, both graft types were incubated in distilled water. Samples of both graft types (100 mm with a 5.0-mm inner diameter) were incubated in these solutions at 37 degrees C for 70 days before environmental scanning electron microscopy, radial tensile strength and quality control, gel permeation chromatography, and in vitro compliance assessments were performed. Oxidative degradation was ascertained from significant changes in molecular weight with respect to a control on all Pulse-Tec grafts treated with t-but/CoCl(2), Glut/t-but/CoCl(2), and plasma fractions I-III. Pulse-Tec grafts exposed to the H(2)O(2)/CoCl(2) mixture had significantly greater compliance than controls incubated in distilled water (p < 0.001 at 50 mmHg). No changes in molecular weight with respect to the control were observed for the CPU samples; only those immersed in t-but/CoCl(2) and Glut/t-but/CoCl(2) showed an 11% increase in molecular weight to 108,000. Only CPU grafts treated with the Glut/t-but/CoCl(2) mixture exhibited significantly greater compliance (p < 0.05 at 50 mmHg). Overall, results from this study indicate that CPU presents a far greater chemical stability than poly(ether)-urethane grafts do. 相似文献
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Standardised epidemiological caries assessments used in oral health surveys have been shown to be poor at predicting whether a tooth surface will be treated restoratively when a patient visits a dentist. However, it has been argued that oral health surveys may be more relevant in determining needs at the level of an individual or groups of individuals. The objective of this study was to determine the discriminatory power of visual caries assessments at two thresholds (D1 & D3) in adolescents of average age 12.1 years to predict experience of dentinal caries 3 years later or the experience of restorative treatment (not re‐treatment) during the 3‐year period. The data was derived from a prospective 3‐year longitudinal study in which the dental care provided by 41 dentists for 403 adolescents was monitored. Dental caries experience was monitored by annual standardised assessments of caries undertaken by a single trained examiner. ROC analysis showed that caries assessed visually at the D1 threshold in 12‐year‐olds was a better predictor (P < 0.001) of experiencing some dentinal caries after 3 years (Az = 0.781) than was caries assessed visually at D3 threshold in 12‐year‐olds (Az = 0.670). Assessing caries visually at either the D1 or the D3 threshold had no discriminatory power for predicting whether an individual would experience some restorative treatment during the ensuing 3‐year period (Az for D1 = 0.507; Az for D3 = 0.518). 相似文献
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Nigel Wynne RGN/Dip BSc Stuart Brand BSc PhD Roy Smith BA PhD 《Journal of advanced nursing》1997,26(3):470-474
There is an ongoing debate in nurse education concerning the role and delivery of the biological sciences in the nursing curriculum. One of the fundamental questions raised by this debate asks how best can teachers impart biological knowledge in a manner that can be readily applied by students and qualified nurses to inform their clinical practice. This paper will include a discussion of some of the features of pre-registration education that may have influenced the manner in which biological sciences are perceived, taught and used by nurses. It will be argued that nursing may have developed a form of incomplete holism and that this may be in part responsible for the challenges that remain to be met within this area of the nursing curriculum. As a response to incomplete holism an innovative approach within pre-registration education will be introduced. This development involves the use of linked teaching sessions which aim to develop the analytical skills necessary to apply physiological knowledge to nursing practice. 相似文献